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New titanium(+4) and vanadium(+5) 8-oxyquinolinate complexes were synthesized. Their structures were determined by X-ray diffraction. The synthesized compounds catalyze the polymerization of ethylene in the presence of Al/Mg activators, {Et2AlCl/Bu2Mg} and {Et3Al2Cl3/Bu2Mg} (up to 3400 kg of PE (mol of [M] h atm)−1), to form ultrahigh-molecular-weight polyethylene with a molecular weight up to 5.3•106 Da. The synthesized compounds are shown to be efficient precatalysts for the synthesis of ethylene-octene copolymers. A high insertion of 1-octene into the copolymer composition, up to 9.5%, was observed for vanadium [bis(7-tert-butyl-2,5-dimethyl-8-oxyquinolinato)]dipropoxide. [ABSTRACT FROM AUTHOR]

A new fluorine-containing OOO2−-type chelating ligand and the titanium(iv) dichloride and bis-isopropoxide complexes with this ligand were synthesized. The structure of the titanium(iv) bis-isopropoxide complex was determined by single-crystal X-ray diffraction analysis. In the presence of Al/Mg activators (Et2AlCl-Bu2Mg or Et3Al2Cl3-Bu2Mg), both complexes catalyze the ethylene polymerization giving ultra-high-molecular-weight polyethylene with a molecular weight of up to 5.8 • 106 Da. Due to a low degree of polymer entanglement, these polymers can be processed by a solvent-free method to prepare high-strength high-modulus films with a Young's modulus up to 117 GPa and a tensile strength up to 2.18 GPa. [ABSTRACT FROM AUTHOR]

A series of novel complexes of titanium(IV) with OSSO-type ligands were synthesized. In the presence of Al/Mg activators such as {Et2AlCl+Bu2Mg} and {Et3Al2Cl3+Bu2Mg}, all the synthezed compounds catalyzed the polymerization of ethylene (with activity up to 2554 kgPE molM–1 h–1 atm–1). The otained ultrahigh-molecular-weight polyethylene (UHMWPE) samples had a molecular weight up to 7.6×106 Da and exhibited high melting points (up to 143°C) and high crystallinity (up to 84%). It was demonstrated that these polymers can be processed by a solvent-free method into high-strength/high-modulus oriented films (with breaking strength up to 2.2 hPa and elastic modulus up to 127.7 hPa). The synthesized compounds further manifested themselves as efficient pre-catalysts (as indicated by their catalytic activity up to 408 kgcopolymer molM–1 h–1 atm–1) for the preparation of ethylene–propylene copolymers with high propylene incorporation (up to 37%). [ABSTRACT FROM AUTHOR]